Google is working on a competitor for Apple’s Siri. It recently acquired Clever Sense, which developed Alfred, a mobile butler app. Rumors have suggested that Google has been working on an AI based personal assistant app ever since Apple unveiled Siri. According to a report by AndroidAndMe, the project is codenamed Majel, a Star Trek reference.

While Google has had Voice Actions since years, it has been neither as accurate, nor as usable as Siri. Siri may have a few flaws of its own, but for now, it is the best mobile virtual assistant you can get.

Google’s Majel will allow users to perform actions and tasks using natural language, not a specific set of commands. Apparently, Majel will be launched in early 2012. I expect it to be unveiled before Google I/O 2012.

Apple’s Siri could be a serious threat to Google’s primary revenue stream – search advertising, if more users just start using it to find stuff instead of using Google’s search. Google’s best bet is to launch a viable competitor to Siri soon, and then find some way to monetize it.

Even Microsoft is already competing with Apple and Google in this game with TellMe on Windows Phone and Voice Commands on the Xbox 360, powered by Kinect.